from math import sqrt
x1, y1, x2, y2 = map(float, input().split())
X = abs(x1 - x2)
Y = abs(y1 - y2)
print(sqrt(X**2 + Y**2)) from math import sqrt x1, y1, x2, y2 = map(float, input().split()) x1 map(float, input().split()) map float input().split() ().split () input split y1 x2 y2 X = abs(x1 - x2) X abs(x1 - x2) abs x1 - x2 x1 x2 Y = abs(y1 - y2) Y abs(y1 - y2) abs y1 - y2 y1 y2 print(sqrt(X**2 + Y**2)) print sqrt(X**2 + Y**2) sqrt X**2 + Y**2 X**2 X 2 Y**2 Y 2 x1, y1, x2, y2 = map(float, input().split()) map(float, input().split()) x1 x2, y2 = map(float, input().split()) map(float, input().split()) x2 X = abs(x1 - x2) abs(x1 - x2) X Y = abs(y1 - y2) abs(y1 - y2) Y y1, x2, y2 = map(float, input().split()) map(float, input().split()) y1 y2 = map(float, input().split()) map(float, input().split()) y2
from math import sqrt
x1, y1, x2, y2 = map(float, input().split())
X = abs(x1 - x2)
Y = abs(y1 - y2)
print(sqrt(X**2 + Y**2))
